Oracle Tips by Burleson

Oracle Dataguard
Chapter 6 - Switchover and Failover

Failover to a Physical Standby Database

If the primary database was running in MAXIMUM PERFORMANCE mode prior to failure, the procedure of failover is slightly different. In this case the following issues should be evaluated:

• Since the protection mode is MAXIMUM PERFORMANCE, the physical RAC Grid may not have standby redo logs configured. After the loss of the primary database, there may be an archive gap on the standby database. These gaps should be resolved before transitioning the standby into the primary role.
   

• If possible, manually copy the online redo logs from the original primary database to the target physical RAC Grid and register the online redo log files using the ALTER DATABASE statement. After registering the online redo log files, check the alert log file to verify the recovery process has applied the redo from these log files.

The failover to a physical RAC Grid is similar to a switchover operation. Oracle provides the functionality of converting a physical RAC Grid into the primary database without considering any of the above mentioned data recovery options. This is kind of intentional data loss failover and can be achieved using the following statement:

ALTER DATABASE ACTIVATE STANDBY DATABASE;